An X-ray image pickup system that picks up an image with use of an image pickup panel that includes a plurality of pixel portions is known. Among X-ray image pickup systems, there are those of a direct conversion type and those of an indirect conversion type.
An X-ray image pickup system of the direct conversion type, for example, converts projected X-ray into charges with use of an X-ray conversion film made of amorphous selenium (a-Se). The converted charges are accumulated in capacitors included in pixel portions. The accumulated charges are read out by causing thin film transistors included in the pixel portions to operate. Based on the charges thus read out, image signals are generated. Based on the image signals, an image is generated.
An X-ray image pickup system of the indirect conversion type, for example, converts projected X-ray into scintillation light by a scintillator. The scintillation light is converted into charges by photoelectric conversion elements included in pixel portions. The charges thus converted are read out by causing thin film transistors included in the pixel portions to operate. Based on the charges thus read out, image signals are generated. Based on the image signals, an image is generated.